If you&apos;ve only taken a quick look, you&apos;ll perhaps have the idea that OpenStreetMap is a competitor to Google maps. It kind of is that, but that&apos;s really not the whole story.

It&apos;s more accurate to compare OpenStreetMap with wikipedia. It is very much the wikipedia of maps. Similar for a number of reasons....

Like wikipedia we do mass collaboration. We have getting on for 400,000 registered users. These people can all edit the map. http://wiki.openstreetmap.org/wiki/Stats

So we have an edit tab. Users can view the map, and then move across to the edit tab enter the editing software. A vector based map editing environment.

Like wikipedia, Openstreetmap is open licensed. All the data is released with an creative commons license

We have an OpenStreetMap foundation. This is a not-for-profit organization. Like wikipedia, we didn&apos;t manage to register as a UK charity because it&apos;s too awkward (The charity commission isn&apos;t geared up to deal with Internet-based good causes) but effectively we&apos;re a charity, or rather we do deserve to be a charity. The foundation is quite small. It doesn&apos;t employ any people, and so there&apos;s relatively little money changing hands. Everyone involved in OpenStreetMap are volunteers.

Including me... Just to introduce myself a little bit. I am a volunteer and enthusiast, active in the OpenStreetMap community in various ways since 2006. I do have a day job. At http://placr.co.uk we do a lot of work with open data, geo technology and transport related stuff. So I do get to use OpenStreetMap sometimes with day to day work, but essentially I do OpenStreetMap in my free time as a volunteer.

What about using OpenStreetMap? Well many web developers will think of the Google maps thing of embedding a map on your website, and you can certainly do that with OpenStreetMap. Here&apos;s a an Oxford University website using embedding “slippy map” JavaScript and showing OpenStreetMap tiles: http://www.ox.ac.uk/applications/dynamic/map.rm?postcode=OX1+3BJ&amp;location=Balliol%20College&amp;id=440

So what&apos;s going on when you embed maps in this way. There&apos;s actually two quite distinct things going on. Javascript on your website will run in the browser to display the panning zooming map interface. This fetches tiles from a tile server. These are little square images which make up the map. When you see OpenStreetMap used in this way, you&apos;ll often see people using a JavaScript library called OpenLayers. It&apos;s a popular because it&apos;s open source and it&apos;s quite good. But it&apos;s a separate project from OpenStreetMap, and in fact there are many different javascript libraries to choose fromfor displaying a slippy map. Computer image from http://www.openclipart.org/detail/90145

You can even use the Google maps Javascript to display OpenStreetMap tiles. This looks a bit weird but you may be interested in following this approach if, for example, you have a whole bunch of marker overlays code already written with Google maps. You can still present OpenStreetMap as a base map, or even just as an alternative choice for your users.

So the message to web developers is, please go ahead and use OpenStreetMap in this way, instead of boring old Google maps. OpenStreetMap tiles are available for free with a creative commons licensee

And mobile developers too. You can bring the OpenStreetMap tiles into mobile apps.

So we have this OpenStreetMap tile server pumping out tiles to various people&apos;s websites (and to the display on OpenStreetMap.org of course) But we&apos;re missing something from this picture...

We have raw map data being processed to create this tiles on the tile server

This is process called rendering. We go from vector data, the geographical coordinates of every point along every road, to a rasterised map image, which then gets chopped up into tiles.

The raw data, as it turns out, is what OpenStreetMap is really all about. We&apos;re open at the raw data level, offering up geo data which underlies the map, via an API and via planet downloads.

So the OpenStreetMap data feeds into the tile server...

But also to an API and to planet downloads. So lets take a look at the API...

This is an XML API which is created in ruby on rails, along with the OpenStreetMap website.

It&apos;s actually a read/write API, so the editing software which allows people to contribute, will write changes back to the database via this API. App developers and web developers can also access the API, for example to request a small bounding box of data. * * This is not really what the API is for. It&apos;s actually primarily to support editor software. Some people in the community also work with the API to do scripted importing. Advanced developers might like to look at providing OSM editing functionality in their apps. But most developers will actually want to look at...

...the planet downloads. This provides all the raw data as a bulk download for the entire planet.

The planet file itself is a bit of a monster. 16Gigabytes of compressed XML. We also publish diff files, so developers can download the planet file once and then sync your data with updates from the community on a minutely basis.

So you might like to look at doing at yourself if you have a server handy, but a nice consequence of this, is that we get this middle tier of servers being set up. Mostly these are by third parties. Extracts mean that you don&apos;t have to download the whole planet. You can get just the UK extract for example. The data gets converted into other useful formats too. You can download OSM data as shapefiles or maps for garmin units. Nominatim is a search service using OSM data (geocoding and reverse geocoding) XAPI is an extended API which allows you to do more flexible querying, for example get all the libraries in London. Think of the mobile apps you could develop with that kind of data.

So we&apos;re starting to see a sort of ecosystem of OpenStreetMap data users

And notice how the OpenStreetMap tile server starts too look like just one small part of this

What about if you wanted to set your own tile server?

This is where things get really pretty! You can run the rendering software yourself, so taking the raw data and creating raster maps. Here you see some examples such as OpenCycleMap.org So you can choose which types of data you want to emphasise. This gives you full cartographic control over the output. There&apos;s a choice of different rendering softwares. For tile servers people are mostly using “Mapnik”.

Setting up your own tile server is a pretty technical process. We&apos;d like to make it easier. But as a web developer this means you start to have a choice of different tile servers. Take a look at open.mapquest.com (and http://developer.mapquest.com/web/products/open/map ) maps.cloudmade.com (and http://developers.cloudmade.com/projects/tiles/documents ) So still displaying OpenStreetMap, but not necessarily taking your tiles from the OpenStreetMap tile server. This limited idea of server tiles (competing with google maps) is only a small part of OpenStreetMap is about

The core purpose of OpenStreetMap is to create and release raw geodata with an open license. Data is at the center of this ecosystem. Around the edge of the diagram is an exploding number of interesting new uses of map data.

Websites. Mobile apps. Navigations systems. 3D rendering experiments. Some of these are commercial enterprises (and you are allowed to use OpenStreetMap for commercial uses) Some are university projects. Some just from “bedroom coders” . Open data enables interesting unexpected uses.

We&apos;re building a map from scratch so that we can release it with an open license. This is a lot of work, so we need a lot of people to join in with mapping. We need people use openstreetmap and expose it to more people, to attract more mappers.

This is an old slide explaining what&apos;s basically going on with OpenStreetMap in relation to Ordnance Survey. As OSM quality improves, at zero cost, it exerts a downward pressure on the price of traditionally licensed datasets

The situations a bit more complicated than that of course This year Ordnance Survey released some of their datasets for free. StreetView is perhaps the most useful. Whether OSM is better or worse than Streetview is debatable , but when you consider that StreetView is a raster map, OSM is potentially much more useful (all depends on your use case) They definitely have NOT released all their dataset for free. The popular landranger, still charged for. MasterMap is the super-detail dataset which you still pay through the nose for as part of the planning process. OSM isn&apos;t really trying to reach the level of detail of MasterMap, but may perhaps exert a downward pressure on their price point.

There&apos;s several ways you can help OpenStreetMap. As I&apos;ve stressed in this talk, we&apos;d like more people to use openstreetmap. This will help attract more people to contribute to the map. If you&apos;d like to join in with mapping in London, follow @OSMLondon on twitter. We like help with developing OpenStreetMap. We need help with the core site and API (particularly ruby on rails pros) , but can get involved as a developer in many and varied areas the ecosystem. Remember it&apos;s effectively a charity. When you help OpenStreetMap you&apos;re doing a good thing.

43.
Harry Wood has been an OpenStreetMap enthusiast, and contributor since 2006. He works as a senior software engineer at http://placr.co.uk on projects relating to transport and GPS data analysis. Previously he worked in a technical and OpenStreetMap community development role at CloudMade. In 2011 he has continued to volunteer for the project in several roles, as mapper, developer, documenter, community coordinator, promoter, and the chief London event organiser. http://harrywood.co.uk These slides are (of course) freely re-usable under the Creative Commons Attribution-ShareAlike 2.0 License Map images cc-by-sa2 OpenStreetMap.org contributors. CloudMade.com, OpenCycleMap.org, whitewater.quaker.eu.org, OSMC Reitkarte, OpenPisteMap.org, öpnvkarte.de, skobbler.de, navmii.com, uktraveloptions.com . Wrecking ball photo http://flic.kr/p/8VETFg by Rhys's Piece Is. Photo of me photo mapping by Gordon Joly http://www.flickr.com/photos/loopzilla/2465042085/ Adapted free clip-art from: thenounproject.com, openclipart.org thedesignsuperhero.co